Cardiovascular risk factor modification in asymptomatic adults and implications for pilots

Abstract

This study aims to examine the available evidence that supports a more aggressive approach to managing asymptomatic people with low to intermediate cardiovascular risks; to evaluate the appropriate threshold for initiating pharmacologic interventions to treat hyperglycaemia, hyperlipidaemia, and hypertension; and to describe the implications for airline pilots. A systematic search was performed employing an OvidSP interface, including all EBM Reviews, EMBASE, and Ovid MEDLINE databases. Data, including sixteen randomised controlled trials, on the appropriate threshold for initiating pharmacologic interventions were extracted. Studies on the treatment of hyperlipidaemia indicated that the threshold for initiation of intervention in intermediate-risk people is a LDL-C level of 3.36 mmol/l (130 mg/dl). There was no lower limit or optimal LDL-C level below which further reduction was no longer beneficial. Studies on the treatment of hyperglycaemia suggested that a threshold of fasting plasma glucose of ≥5.3 mmol/l (95 mg/dl) and 2-hour postprandial glucose level of 7.8 mmol/l (140 mg/dl) is reasonable for initiating pharmacologic intervention. Initiating treatment to people with a blood pressure of ≥130/≤89 mmHg or ≤139/≥85 mmHg significantly reduced the risk of developing stage 1 hypertension. Multifactorial intervention studies showed that, in hypertensive patients (BP ≥160/≥100 mmHg), initiating treatment to those with a total cholesterol of 6.5 mmol/l (251.35 mg/dl) or higher resulted in a significant reduction in the risk of developing fatal and non-fatal cardiovascular events. The available evidence from large quality trials supports a more aggressive approach to managing hyperglycaemia, hyperlipidaemia, and hypertension in asymptomatic pilots with a 5-year CVD risk of 5-10% and 10-15%.